Active vibration control systems are used to reduce or cancel noise and vibrations induced by internal combustion engines of vehicles. Active vibration control systems utilize active actuators, such as active engine mounts, to cancel the engine induced vibrations.
One such active engine mount comprises a spring-mass system such as an electromagnetic actuator having an electromagnet and piston. The electromagnetic actuator is electromagnetically driven and operable to generate a neutralizing force in response to forces transmitted to the chassis or body it is mounted on. However, in order to effectively cancel the transmitted or resultant forces, the neutralizing force must be tuned to the amplitude and frequency of the transmitted force. While numerous methods and apparatuses have been developed for generating such a neutralizing force, in all known developments, generating the neutralizing force is achieved independently. That is, independent mechanisms (e.g., additional sensors) are employed in order to tune the frequency of the neutralizing force to the frequency of the resultant forces (which is a function of the rotational speed of the crankshaft). Such independent mechanisms often require expensive and complex control units to effectively cancel engine induced forces.
Accordingly, it is desirable to provide improved methods and systems for controlling an active engine mount. In addition, it is desirable to provide methods and systems for controlling an active engine mount without the need for additional sensors. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.